In a NoDB app? It's very easy: only one code base ever directly touches the data, because the data lives in the RAM allocated to the app. You give external access via an API, so integrity is very easy to enforce.
But one has to wonder, what happens when you need to upgrade the app? Shutting down the process and destroying the memory image doesn't seem like the best option:
- First, it disrupts connected applications since the process is killed, introducing downtime.
- Second, when starting up again in say version 2, the data that will be loaded in memory still needs to be transformed in the format expected by version 2. This transformation can take time on large data, introducing further downtime.
The challenge would be to eliminate this downtime by combining a solution for both client disruption and state transfer. A data abstraction like a database using SQL can simplify such a solution.